CVE-2022-44365 is a critical stack overflow vulnerability identified in the Tenda i21 router firmware version V1.0.0.14(4656). The vulnerability is triggered via the /goform/setSysPwd endpoint, which is likely responsible for setting the system password on the device. A stack overflow occurs when more data is written to a buffer located on the stack than it can hold, potentially allowing an attacker to overwrite adjacent memory, leading to arbitrary code execution or system crashes. Given that this vulnerability is remotely exploitable over the network (AV:N), requires no privileges (PR:N), and no user interaction (UI:N), it presents a significant risk. The CVSS v3.1 base score of 9.8 reflects the high impact on confidentiality, integrity, and availability, indicating that successful exploitation could allow an unauthenticated attacker to fully compromise the device. The vulnerability falls under CWE-787 (Out-of-bounds Write), a common and dangerous class of memory corruption bugs. Although there are no known exploits in the wild as of the published date, the ease of exploitation and critical severity make it a high-priority issue. The lack of vendor or product details beyond the Tenda i21 model limits the scope of affected devices, but the vulnerability specifically targets this router firmware version. No patches or mitigations have been linked or published at this time, increasing the urgency for affected users to apply any forthcoming updates or implement compensating controls.

For European organizations, the exploitation of CVE-2022-44365 could lead to complete compromise of affected Tenda i21 routers, which are commonly used in small office/home office (SOHO) environments and possibly in some enterprise edge deployments. A successful attack could result in unauthorized access to internal networks, interception or manipulation of network traffic, and potential pivoting to other internal systems. This threatens confidentiality by exposing sensitive data, integrity by allowing modification of network configurations or injected malicious payloads, and availability by causing device crashes or denial of service. Given the critical nature of the vulnerability and the lack of authentication requirements, attackers could remotely exploit vulnerable devices without user interaction, increasing the risk of widespread compromise. European organizations relying on Tenda i21 routers for network connectivity or security may face operational disruptions, data breaches, and reputational damage. Additionally, critical infrastructure or government entities using these devices could be targeted for espionage or sabotage, especially in the context of heightened geopolitical tensions in Europe.

1. Immediate Network Segmentation: Isolate Tenda i21 routers from critical network segments to limit potential lateral movement if compromised. 2. Disable Remote Management: If remote management features are enabled on the affected devices, disable them to reduce the attack surface. 3. Monitor Network Traffic: Implement IDS/IPS rules to detect anomalous requests to the /goform/setSysPwd endpoint or unusual traffic patterns indicative of exploitation attempts. 4. Firmware Updates: Continuously monitor Tenda’s official channels for firmware updates or security patches addressing this vulnerability and apply them promptly. 5. Access Control: Restrict access to router management interfaces to trusted IP addresses only, using firewall rules or VPNs. 6. Incident Response Preparedness: Prepare for potential incidents by backing up router configurations and having a recovery plan to restore devices quickly if compromised. 7. Vendor Engagement: Engage with Tenda support or distributors to obtain detailed information about affected versions and patch availability. 8. Alternative Hardware Evaluation: For critical environments, consider replacing vulnerable Tenda i21 devices with routers from vendors with stronger security track records and timely patching.